Champaigne Christensen, 18, and her friends often attend the under-21 events, and watch the drama when the bars close at 2 a.m.

“The trouble starts with the gang members that come down here and have fun,” said Christensen.

Under pressure, some downtown bars have agreed to end under-21 events.

Teens we spoke to don’t like it and say they’re being unfairly targeted.

“We don’t gang bang. Why we can’t go to the club? We want to party, too. Why you gotta be 21 to go to the club? We should be able to go the club any time we want to,” said downtown visitor Tierra Perry. “Why do they want to punish everybody for some of the immature teens?”

City regulators are now meeting with downtown clubs to curb the violence and tighten controls on underage drinking. But Samuels says the city’s patience is gone.

“If these clubs do not abide by the rules, we will shut them down,” said Samuels.

The crackdown started Sunday, but it’s only the beginning.

Mayor R.T. Rybak and City Council members are writing new laws to give the city more power to impose conditions on liquor licenses — even take them away.